When securing a tube to a cross member, the strength and durability of the attachment may be important. Depending on the specific dimensions of the tube and the cross member, and depending on the amount of force that will be applied to the attachment, the attachment may fail if it is not strong enough.
Existing attachment techniques include welding or fastening the cross member to the exterior of the tube/bar/channel. When fastening, a hole is drilled in the exterior of the tube and a fastener is inserted through the exterior of the tube and is secured to a bolt on the inside of the tube. Both the welding technique and fastener technique provide load and tension strength, but both are weak against lateral or sheer forces, rotational forces and moment forces.